Petrov: Mancini has transformed Man City thinking
Petrov struck in Saturday's victory over Stoke City on Mancini's debut as coach.
"Every manager has different ideas and Roberto is trying to do more tactical stuff from corners and free-kicks," he said.
"That is good for us because the last three games before yesterday we have conceded nine goals, mostly from free-kicks and corners, which is too much.
"We know we can do better than that and, in the future, I am sure we will."